Tow/Haul

I'm curious about the Tow/Haul mode in the Silverado. I realize it firms up the shifts and is an aid in towing, I guess I was wondering if it is taking some of the TM out of the tranny or how it works. Can you safely drive in Tow/Haul mode all the time if desired?

I think it just firms up the line pressure and changes the shift points. I don't believe it takes any TM out.

If you want better driveability, get a tune. I had 80% of TM taken out of mine and it made it a different truck.

I think my manual (2001) says using t/h mode when you're not towing or hauling doesn't cause any damage, but might burn more gas. Along with firming shifts, it raises shift points and makes the trans kick down earlier under load. It also seems to change converter lockup. I use it when going up and down mountain passes, and on the downhill side it feels like there's more engine braking (in the same gear) with tow/haul.